Because users of the web often find themselves inundated with advertisements that may not be relevant to their interests, users may increasingly ignore advertisements. This in turn may lead to a reduced return on the advertising investments of those companies and individuals who seek to advertise products and/or services on the web. Moreover, although certain data regarding online users may be available, advertisers may be reluctant to employ such data to more narrowly target advertisements to users due to concerns about data accuracy and/or privacy.